Evaluation of cervico-occlusal dimensions of maxillary and mandibular incisor brackets for lingual orthodontics.

AIM: The purpose of this study was to analyze the cervico-occlusal dimensions of brackets used in lingual orthodontics for maxillary and mandibular central and lateral incisors, to compare them with the numbers informed by the manufacturer. MATERIALS AND METHODS: The brackets were placed in a template and analyzed by scanning electron microscopy (SEM), evaluating the images with the aid of a software that allowed determination of reference points, tracing of lines on the bracket images and measurement of the distances. RESULTS: Brackets manufactured by Dm Ceosa Hiro, Tecnident PSWb and Dentaurum Magic did not present statistically significant differences between the mean values of slot heights and the values informed by manufacturers. Conversely, the brands Ormco 7th generation, Ormco STb, GAC Innovation L, ORJ-ORG, Tecnident, Ormco STb LSW and Adenta evolution STL exhibited statistically significant differences. CONCLUSION: In general, there was a deficiency in the standar-dization of cervico-occlusal measurements of slots of the brackets analyzed. CLINICAL SIGNIFICANCE: Manufacturers should be attentive to the quality control of their materials. Future studies will analyze the actual clinical influence of these findings on the orthodontic mechanics.

Upper incisors' positions after extraction.

The aim of this research was to verify the amount of horizontal and vertical movement and incisor inclination of upper incisors and correlate these with Edgewise and Alexander brackets use and the presence of overbite during anterior retraction in sliding mechanics. The sample was composed of 40 adult patients divided into 2 groups, treated with Edgewise and Alexander brackets (20 each) subdivided in 2 groups (10 each), according to the presence or absence of deep bite. Treatment consisted of 4 extraction cases with sliding mechanics with the 2 different brackets. Pre- and post-treatment cephalograms were measured and the values of interest submitted to descriptive statistical analysis, ANOVA at 5%, the Tukey test and Pearson's correlation. Upper incisor retraction was not related to the brackets used nor to the presence of deep bite, though lingual tipping was greater when Edgewise brackets were used and deep bite was absent. No statistically significant differences in upper incisor vertical movements were observed and no correlation was determined between upper incisor intrusion and lower incisor labial tipping in overbite correction or in upper incisor retraction and lower incisor labial tipping for overjet correction. Bracket prescription and its interaction with deep bite were significant and Edgewise brackets without deep bite showed the worst inclination control. It was concluded that bracket prescriptions are important to increase control of sliding mechanics.

Biomechanical analysis of total arch maxillary distalization using infrazygomatic crest miniscrews: a finite element analysis study.

AIM: To evaluate the maxillary incisors and canine's immediate movement tendency using three different power arms (PA) height levels during total arch maxillary distalization supported on infrazygomatic crest (IZC) miniscrews according to finite element analysis (FEA). METHODS: Three finite element models of the maxilla were developed based on CBCT imaging of a teenage male patient presenting a Class II Division 1 malocclusion in the early permanent dentition. Maxillary complex, periodontium, orthodontic accessories, IZC miniscrews and an orthodontic wire were digitally created. The PAs were placed between canines and lateral incisors and projected at 4, 7, and 10 mm height distances. After that, distalization forces were simulated between PA and IZC miniscrews. RESULTS: The anterior teeth deformation produced in the FEA models was assessed according to a Von Mises equivalent. The stress was measured, revealing tendencies of initial maxillary teeth movement. No differences were found between the right and left sides. However, there was a significant difference among models in the under-stress areas, especially the apical and cervical root areas of the maxillary anterior teeth. More significant extrusion and lingual tipping of incisors were observed with the 4 mm power arm compared to the 7 mm and 10 mm ones. The 10 mm power arm did not show any tendency for extrusion of maxillary central incisors but a tendency for buccal tipping and intrusion of lateral incisors. CONCLUSION: The maxillary incisors and canines have different immediate movement tendencies according to the height of the anterior point of the en-masse distalization force application. Based on the PA height increase, a change from lingual to buccal tipping and less extrusion tendency was observed for the incisors, while the lingual tipping and extrusion trend for canines increased.

Mini-Implant Screws for Bone-Borne Anchorage: A Biomechanical In Vitro Study Comparing Three Diameters.

PURPOSE: To evaluate the maximum strength and the maximum aperture supported by mini-implant screws of three different diameters in an in vitro rapid maxillary expander model. MATERIALS AND METHODS: Fifteen appliances were mounted in artificial bone polyurethane blocks. In each appliance, a Hyrax expander anchored by four mini-implant screw sets of three different diameters were divided into: group 1 (n = 5), 1.8-mm-diameter screws; group 2 (n = 5), 2.0-mm-diameter screws; and group 3 (n = 5), 2.2-mm-diameter screws. All sets (bone blocks + expander + four mini-implants) were inserted into a customized and standardized device that simulated a mid-palate disjunction. The expanders were activated to mechanically test the insertion of the mini-implant into the devices until breakage or deflection of screws occurred. The number of activations, the maximum supported strength, and the maximum expander aperture values until failure were recorded for each group. Data were subjected to a Student t test at a significance level of 5%. RESULTS: There were no significant differences between the groups regarding the number of activations up to the maximum supported strength. The expander achieved aperture values where differences were slightly significant just between groups 1 and 2 (P = .048). There was a significant difference between groups 1 and 3 regarding the maximum supported load (P = .039). CONCLUSION: Regardless of the mini-implant screw diameters, the expander device used in this anchorage system model withstood strengths and aperture rates beyond those that may be required during clinical rapid maxillary expansion.

Cervical vertebrae maturation index estimates on cone beam CT: 3D reconstructions vs sagittal sections.

OBJECTIVES: The aim of this study was to evaluate the performance of CBCT three-dimensional (3D) reconstructions and sagittal sections for estimates of cervical vertebrae maturation index (CVMI). METHODS: The sample consisted of 72 CBCT examinations from patients aged 8-16 years (45 females and 27 males) selected from the archives of two private clinics. Two calibrated observers (kappa scores: ≥0.901) interpreted the CBCT settings twice. Intra- and interobserver agreement for both imaging exhibition modes was analyzed by kappa statistics, which was also used to analyze the agreement between 3D reconstructions and sagittal sections. Correlations between cervical vertebrae maturation estimates and chronological age, as well as between the assessments by 3D reconstructions and sagittal sections, were analyzed using gamma Goodman-Kruskal coefficients (α = 0.05). RESULTS: The kappa scores evidenced almost perfect agreement between the first and second assessments of the cervical vertebrae by 3D reconstructions (0.933-0.983) and sagittal sections (0.983-1.000). Similarly, the agreement between 3D reconstructions and sagittal sections was almost perfect (kappa index: 0.983). In most divergent cases, the difference between 3D reconstructions and sagittal sections was one stage of CVMI. Strongly positive correlations (>0.8, p < 0.001) were found not only between chronological age and CVMI but also between the estimates by 3D reconstructions and sagittal sections (p < 0.001). CONCLUSIONS: Although CBCT imaging must not be used exclusively for this purpose, it may be suitable for skeletal maturity assessments.

Efficiency of two protocols for maxillary molar intrusion with mini-implants.

OBJECTIVE: The aim of this study was to compare the efficiency of two protocols for maxillary molar intrusion with two or three mini-implants. METHODS: Twenty five maxillary first molars extruded for loss of their antagonists in adult subjects were selected. The sample was divided into two groups, according to the intrusion protocol with two or three mini-implants. Group 1 consisted of 15 molars that were intruded by two mini-implants. Group 2 consisted of 10 molars intruded by three mini-implants. Changes with treatment were analyzed in lateral cephalograms at the beginning and at the end of intrusion of maxillary molars. RESULTS: Results showed that there was no difference in efficiency for the two intrusion protocols. It was concluded that extruded maxillary molars can be intruded with two or three mini-implants with similar efficiency.

Halogen light versus LED for bracket bonding: shear bond strength.

INTRODUCTION: LED light-curing devices seek to provide a cold light activator which allows protocols of material polymerization with shorter duration. OBJECTIVE: The present study aimed to evaluate the shear bond strength of bracket bonding using three types of light-curing devices: One with halogen light (Optilight Plus - Gnatus) and two with LEDs (Optilight CL - Gnatus and Elipar Freelight - 3M/ESPE). RESULTS: Comparing the results by analysis of variance, the Gnatus LED device showed an inferior statistical behavior in relation to other light sources, when activated by a short time. But, when it was used for 40 seconds, the polymerization results were consistent with the other evaluated sources. The device with the best average performance was the halogen light, followed by the 3M/ESPE LED. CONCLUSION: It was concluded that the LEDs may be indicated in orthodontic practice, as long as a protocol is used for the application of light with the activation time of 40 seconds.

Are torque values of preadjusted brackets precise?

OBJECTIVE: The aim of the present study was to verify the torque precision of metallic brackets with MBT prescription using the canine brackets as the representative sample of six commercial brands. MATERIAL AND METHODS: Twenty maxillary and 20 mandibular canine brackets of one of the following commercial brands were selected: 3M Unitek, Abzil, American Orthodontics, TP Orthodontics, Morelli and Ortho Organizers. The torque angle, established by reference points and lines, was measured by an operator using an optical microscope coupled to a computer. The values were compared to those established by the MBT prescription. RESULTS: The results showed that for the maxillary canine brackets, only the Morelli torque (-3.33º) presented statistically significant difference from the proposed values (-7º). For the mandibular canines, American Orthodontics (-6.34º) and Ortho Organizers (-6.25º) presented statistically significant differences from the standards (-6º). Comparing the brands, Morelli presented statistically significant differences in comparison with all the other brands for maxillary canine brackets. For the mandibular canine brackets, there was no statistically significant difference between the brands. CONCLUSIONS: There are significant variations in torque values of some of the brackets assessed, which would clinically compromise the buccolingual positioning of the tooth at the end of orthodontic treatment.

Breastfeeding and non-nutritive sucking patterns related to the prevalence of anterior open bite in primary dentition.

OBJECTIVE: Nutritional, immunological and psychological benefits of exclusive breastfeeding for the first 6 months of life are unequivocally recognized. However, mothers should also be aware of the importance of breastfeeding for promoting adequate oral development. This study evaluated the association between breastfeeding and non-nutritive sucking patterns and the prevalence of anterior open bite in primary dentition. MATERIAL AND METHODS: Infant feeding and non-nutritive sucking were investigated in a 3-6 year-old sample of 1,377 children, from São Paulo city, Brazil. Children were grouped according to breastfeeding duration: G1--non-breastfed, G2--shorter than 6 months, G3--interruption between 6 and 12 months, and G4--longer than 12 months. Three calibrated dentists performed clinical examinations and classified overbite into 3 categories: normal, anterior open bite and deep bite. Chi-square tests (p<0.05) with odds ratio (OR) calculation were used for intergroup comparisons. The impact of breastfeeding and non-nutritive sucking on the prevalence of anterior open bite was analyzed using binary logistic regression. RESULTS: The prevalence estimates of anterior open bite were: 31.9% (G1), 26.1% (G2), 22.1% (G3), and 6.2% (G4). G1 would have significantly more chances of having anterior open bite compared with G4; in the total sample (OR=7.1) and in the subgroup without history of non-nutritive sucking (OR=9.3). Prolonging breastfeeding for 12 months was associated with a 3.7 times lower chance of having anterior open bite. In each year of persistence with non-nutritive sucking habits, the chance of developing this malocclusion increased in 2.38 times. CONCLUSIONS: Breastfeeding and non-nutritive sucking durations demonstrated opposite effects on the prediction of anterior open bite. Non-breastfed children presented significantly greater chances of having anterior open bite compared with those who were breastfed for periods longer than 12 months, demonstrating the beneficial influence of breastfeeding on dental occlusion.

Efficiency of two protocols for maxillary molar intrusion with mini-implants

ABSTRACT Objective: The aim of this study was to compare the efficiency of two protocols for maxillary molar intrusion with two or three mini-implants. Methods: Twenty five maxillary first molars extruded for loss of their antagonists in adult subjects were selected. The sample was divided into two groups, according to the intrusion protocol with two or three mini-implants. Group 1 consisted of 15 molars that were intruded by two mini-implants. Group 2 consisted of 10 molars intruded by three mini-implants. Changes with treatment were analyzed in lateral cephalograms at the beginning and at the end of intrusion of maxillary molars. Results: Results showed that there was no difference in efficiency for the two intrusion protocols. It was concluded that extruded maxillary molars can be intruded with two or three mini-implants with similar efficiency.

RESUMO Objetivo: o objetivo do presente estudo foi comparar a eficiência de dois protocolos de intrusão de molares superiores com dois e três mini-implantes. Métodos: foram selecionados 25 primeiros molares superiores extruídos por perda de seus antagonistas, de pacientes adultos. A amostra foi dividida em dois grupos, de acordo com o protocolo de intrusão, com dois ou três mini-implantes: o Grupo 1 consistiu de 15 molares que sofreram intrusão com dois mini-implantes; o Grupo 2 foi constituído por 10 molares intruídos por três mini-implantes. As alterações com o tratamento foram analisadas em telerradiografias em norma lateral ao início e ao final da intrusão dos molares superiores. Resultados: os resultados mostraram que não houve diferença na eficiência dos dois protocolos de intrusão. Concluiu-se que molares superiores extruídos podem ser intruídos, com eficiência semelhante, por meio de dois ou três mini-implantes.

Metallographic analysis of the internal microstructure of orthodontic mini-implants.

Effective orthodontic anchorage may be obtained by miniimplants inserted into the maxillary bones. However, the risk of miniimplant failure is one of the most important issues, especially the rupture of its structure referred to as fracture, mainly due to metal deficiencies. This study analyzed the internal microstructure of orthodontic mini-implants, ascertaining the composition of the metal to detect possible discontinuities from the surface to the core of the screws. Eighteen samples of mini-implants, of 3 different brands, were obtained. The samples were cold-embedded in methyl methacrylate polymer, and were sectioned both longitudinally (3 samples of each brand) and transversely (the other 3 screws of each brand). After preparation, the samples were observed using a light microscope at up to 2,000 x magnification. The results showed that the mini-implants thus analyzed were composed of an Alpha-Beta globular phase of titanium alloy, patterns A1 and A9 (in accordance with the "Technical Committee of European Titanium Producers"). The miniimplants did not present any defects such as bubbles, imperfections or fissures, in either longitudinal or transverse sections, in their internal microstructure. All samples met the requirements of international norms. Orthodontists must be aware of the metal composition and internal microstructure of mini-implants, to decrease the risk of fractures.

Colagem indireta de bráquetes: apresentação de uma técnica passo a passo / Indirect bonding: a step-by-step technique

O emprego da colagem indireta tem se demonstrado um avanço na Ortodontia, uma vez que erros no posicionamento dos braquetes interferem diretamente no resultado final, bem como aumentam o tempo de tratamento. Esta técnica permite melhor visualização em todos os planos espaciais e, portanto, uma acurada padronização na fase de colagem. Apesar de todos os benefícios advindos do uso desta técnica, ainda há poucos ortodontistas adeptos da colagem indireta, talvez por falta de preparo técnico para uma execução adequada. Pelos motivos acima descritos, o objetivo deste manuscrito é apresentar, passo a passo, uma técnica de colagem indireta de braquetes na superfície vestibular dos dentes.

The use of indirect bonding technique has become an advance in Orthodontics, since bracket positioning errors directly affect the final result and increase treatment time. This technique allows better visualization in all spatial plans and, hence, accurate standardization in the bonding stage. Nevertheless, despite all benefits with using this technique, few orthodontists are still willing to perform indirect bonding, perhaps because of lack of technical training for proper development. For these reasons, the aim of this manuscript was to describe an indirect bracket bonding technique on the labial surfaces of the teeth, step-by-step.

Halogen light versus LED for bracket bonding: shear bond strength

INTRODUCTION: LED light-curing devices seek to provide a cold light activator which allows protocols of material polymerization with shorter duration. OBJECTIVE: The present study aimed to evaluate the shear bond strength of bracket bonding using three types of light-curing devices: One with halogen light (Optilight Plus - Gnatus) and two with LEDs (Optilight CL - Gnatus and Elipar Freelight - 3M/ESPE). RESULTS: Comparing the results by analysis of variance, the Gnatus LED device showed an inferior statistical behavior in relation to other light sources, when activated by a short time. But, when it was used for 40 seconds, the polymerization results were consistent with the other evaluated sources. The device with the best average performance was the halogen light, followed by the 3M/ESPE LED. CONCLUSION: It was concluded that the LEDs may be indicated in orthodontic practice, as long as a protocol is used for the application of light with the activation time of 40 seconds.

INTRODUÇÃO: os aparelhos de fotopolimerização por LED buscam proporcionar uma luz ativadora fria, que possibilite protocolos de polimerização do material com menor tempo de duração. OBJETIVO: avaliar a resistência à tração da colagem de braquetes, utilizando três tipos de aparelhos fotoativadores: um de luz halógena (Optilight Plus - Gnatus) e outros dois de LED (Optilight CL - Gnatus; e Elipar Freelight - 3M/Espe). RESULTADOS: comparando os resultados por meio da análise de variância, o aparelho de LED Gnatus apresentou comportamento estatístico inferior em relação às outras fontes de luz, quando ativado por tempo reduzido. Já quando foi utilizado o tempo de 40 segundos, os resultados de polimerização foram compatíveis com as demais fontes avaliadas. O aparelho que apresentou melhor desempenho médio foi o de luz halógena, seguido pelo LED 3M/Espe. CONCLUSÃO: concluiu-se que os LEDs podem ser indicados na prática ortodôntica, uma vez que seja utilizado um protocolo de aplicação da luz com tempo de ativação de 40 segundos.

Tratamiento no quirúrgico de las mordidas abierta esqueletales: utilización adecuada del anclaje con mini-implantes / Nonsurgical treatment of open bites skeletal: anchor with proper use mini-implants

En este estudio se estableció de acuerdo a diferentes investigaciones el método más eficaz y que nos produce menos recidiva en las mordidas abiertas anteriores con un patrón de crecimiento vertical. El método utilizado fue el de los mini-implantes. Es recomendable que las mordidas abiertas anteriores esqueléticas, en pacientes portadores de crecimiento vertical, sean corregidas preferencialmente por la intrusión de los dientes posteriores y no por la extrusión de los dientes anteriores, para evitar perjuicios estéticos. Los mini-implantes proporcionan anclaje absoluto en los molares y muestran mejores resultados. La recidiva de los dientes posteriores intruidos y la extrusión de los elementos anteriores son efectos indeseables generalmente relatados, con mayor frecuencia para otros tipos de aparatología como son magnetos, bite-blocks y aparatos removibles. Pero, ocurre con menor frecuencia en tratamientos con mini-implantes. Con el propósito de demostrar la indicación de estos dispositivos de anclaje absoluto, será relatado un caso clínico de un paciente con mordida cruzada posterior, mordida abierta esquelética y crecimiento vertical, de 17 años de edad, que no quería someterse a tratamiento quirúrgico, al cual se realizó disyunción con una aparatología de Haas, elásticas de 4 onzas de 3/16 para ayudar a realizar la rotación anti-horaria de la maxila y mini-implantes ortodóncicos auto-perforantes de titanio, con perfil transmucoso corto de 1mm de 1,6mm y una longitud de 8,0mm, tipo de cabezal de alta utilidad Pot™.

In this study the most effective method was established in agreement to different investigations and the one that produced less relapse to the anterior open bites with a pattern of vertical growth. The method used was the mini- implant. It is recommendable that skeletal anterior open bites, in patients with vertical growth pattern, are corrected preferentially by the intrusion of posterior teeth and not by the extrusion of anterior teeth to avoid aesthetic damages. The mini-implants provide absolute anchorage in molars and yield better results. Relapse of the anterior teeth with intrusion and the extrusion of the posterior teeth are generally undesirable effects related, with greater frequency for other types of orthodontic devices such as magnets, bite-blocks and removable devises. However, it happens with smaller frequency in treatments with mini-implant. To demonstrate the indication of these adjuncts for absolute anchorage, a clinical case report of a 17-year-old patient with posterior crossbite, skeletal anterior open bite and vertical growth pattern, who did not want to undergo surgical treatment, will be presented. Orthodontic treatment consisted of a disjunction with Haas expander, elastic of 4 ounces of 3/16 to help making the anti-clockwise rotation of the maxilla and self-drilling titanium orthodontic mini-implants, with short transmucosal profile of 1mm of 1,6mm and 8,0mm in length, type of head High Utility Pot™.

Evaluation of proximal enamel thickness and crown measurements in maxillary first premolars

Estimating enamel thickness and planning the resultant optimal morphology of premolars aresubstantial steps before interproximal stripping. Aim: To analyze proximal enamel thickness andcrown measurements in maxillary premolars. Methods: The mesiodistal, buccolingual andcervico-occlusal measurements of 40 human maxillary first premolars (20 right, 20 left) wereregistered with a digital caliper. The teeth were embedded in acrylic resin and sectioned mesiodistallyat the level of the contact areas to obtain 1 mm-thick central sections. Enamel thickness on theproximal surfaces was measured using a perfilometer. Measurements were compared by theStudent’s t-test (α = 0.05). Results: The mean enamel thickness on the mesial surface was 1.22mm for the right (± 0.17) and left (± 0.18) sides. On the distal surface, the corresponding valueswere 1.28 mm (± 0.19) on the right side and 1.39 mm (± 0.17) on the left side. Mean values, inmillimeters, for the mesiodistal, buccolingual and cervico-occlusal measurements on both sidesranged from 7.03 (± 0.43) to 7.07 (± 0.48), 9.59 (± 0.48) to 9.65 (± 0.58) and 8.65 (± 0.66) to8.85 (± 0.65), respectively. There were no significant differences between right and left teeth.However, enamel thickness was significantly greater (p<0.05) on the distal surface. Conclusions:In maxillary first premolars, considering the greater thickness of distal enamel, interproximalstripping during orthodontic treatment may be more pronounced on this surface. The greatestmean value was observed for the buccolingual crown measurement, followed by the cervicoocclusaland mesiodistal dimensions.

Orthodontic retainers: analysis of prescriptions sent to laboratories

OBJECTIVE: To investigate the most commonly fabricated orthodontic retainers. METHODS: Information on the type and amount of maxillary and mandibular retainers produced in a three-month period was collected from six laboratories in the cities of São Paulo, Mauá and Guarulhos - Brazil. The retainers were grouped according to the total production. For the maxillary arch, the groups were: 1S - Begg retainer, 2S - Hawley retainer, 3S - transpalatal arch retainer, 4S - buccal resin-arch retainer and 5S - vacuum-formed retainer, Planas appliance, bonded lingual retainer and V-loop bonded lingual retainer. The groups relative to the mandibular arch were: 1I - 3-3 bonded lingual retainer (canine to canine), 2I - Hawley retainer and V-loop bonded lingual retainer, 3I - Begg retainer, 4I - buccal resin-arch retainer, vacuum-formed retainer and Planas appliance. The data were presented in box plots. Groups were compared using the Student's-t test with Bonferroni correction. RESULTS: The average of maxillary appliances fabricated ranged from 189.5 (1S) to 3.95 (5S). There were significant differences between groups 1S versus 5S and 2S versus 5S (p < 0.0001). Mean values for the mandibular retainers ranged from 55.3 (1I) to 4.2 (4I). Significant difference was observed between groups 2I and 4I (p < 0.0001). CONCLUSIONS: For the maxillary arch, the most requested retainers were Begg and Hawley retainers. Regarding the mandibular arch, bonded lingual retainers and Hawley retainer were the most frequent ones.

Comparative analysis of load/deflection ratios of conventional and heat-activated rectangular NiTi wires

OBJECTIVE: This study compared the load-deflection ratios between 0.019 x 0.025-in rectangular orthodontic wires using 5 conventional preformed nickel-titanium (NiTi) and 5 heat-activated NiTi archwires from four different manufacturers (Abzil, Morelli, 3M Unitek and Ormco), totaling 40 archwires. The archwires were placed in typodonts without tooth # 11 and tested using a universal testing machine connected to a computer. RESULTS: The comparisons of mean load-deflection values of conventional NiTi wires revealed that the lowest mean-deflection ratio was found for 3M Unitek, followed by Ormco, Morelli and Abzil. Regarding the heat-activated wires, the lowest load-deflection ratio was found for Ormco, followed by 3M Unitek, Abzil, and Morelli. CONCLUSION: The comparison of mean load-deflection ratios revealed that the heat-activated wires had lowest mean load-deflection ratios, and this trend was seen during all the study. However, at 2-mm deflection, mean load-deflection ratios for heat-activated Morelli and conventional 3M Unitek wires were very similar, and this difference was not statistically significant.

Características faciales y oclusales en niños con hábitos bucales / Occlusal and facial features in childrenwith oral habits

Fueron analizadas asociaciones entre tipos faciales, características oclusales y hábitos bucales. La muestra consistió de 1.923 escolares de 8 a 12 años (959 niñas, 964 niños) de Campo Grande, MS-Brasil. Comparaciones entre las características evaluadas según los hábitos fueron realizadas por testes de proporción e Chi-cuadrado (a = 5%). La prevalencia de hábitos fue de 37,4%. Hubo diferencia entre géneros, 55% (femenino) y 45% (masculino). Las mayores prevalencias fueron verificadas en el grupo de 8 años (32%) y en los colegios particulares (40,9%). Oñicofagia fue el más prevalente (71,7%), seguida por succión digital (9,7%) e interposición lingual (6,4%). En la mayoría de los grupos de hábitos, se observaron elevadas frecuencias de simetría facial (81-100%). En los que hacían succión digital, los tipos dolicofacial (46%) y mesofacial (43%) fueron significativamente más prevalentes, así como en los que presentaban interposición lingual, con respectivos porcentajes de 54% e 39%. De los portadores de hábitos, 76,9% tenían competencia labial. Las prevalencias de perfil convexo fueron significantemente más altas en los grupos de interposición lingual (85%), succión digital (83%) y oñicofagia (77%). En ellos, las prevalencias de overjet (52%) y trepase vertical (45%) normales fueron significativamente elevadas; sin embargo, en los alumnos con interposición lingual, la mordida abierta anterior fue la más prevalente (67%). La mordida cruzada posterior no fue asociada a los hábitos. A pesar del histórico de hábitos en 720 escolares, hubo asociación con simetría facial, tipos dolicofacial y mesofacial, competencia labial y perfil convexo. No se observó el predominio de maloclusiones.

Associations among facial types, occlusal features and oral habits were analyzed. The sample consisted of 1,923 students aged 8 to 12 years old (959 girls, 964 boys) from Campo Grande, MS-Brazil. Comparisons among the studied characteristics, which were evaluated according to the habits, were carried out using ratio and Chi-square tests (a = 5%). The prevalence of oral habits was 37.4%. There was a difference between genders: 55% for females and 45% for males. The highest prevalence was observed in the group of eight-year-olds (32%) and in private schools (40.9%). Nail biting was the most prevalent habit (71.7%), followed by digit-sucking (9.7%) and tongue thrusting (6.4%). In most of the habit groups, high frequencies of facial symmetry were observed (81-100%). In those who had digit-sucking habit, dolichofacial (46%) and mesofacial (43%) patterns were significantly more prevalent, as well as in those which presented tongue thrusting, with percentages of 54% and 39%, respectively. Of the habit holders, 76.9% presented lip competence. The prevalence of convex profile was significantly higher in the groups of tongue thrusting (85%), digit-sucking (83%) and nail biting (77%). In those students, frequencies of normal overjet (52%) and overbite (45%) were significantly great; but, in the group with tongue thrusting, anterior open bite was the most prevalent feature (67%). Posterior crossbite was not associated with the habits. Despite the history of habits in 720 students, there was an association with the facial symmetry, dolichofacial and mesofacial patterns, lip competence and convex profile. Malocclusions predominance was not observed.

Utilização da imagem da ressonância magnética no diagnóstico das alterações da ATM / Use of magnetic resonance imaging in the diagnosis of changes in TMJ

A disfunção temporomandibular (DTM) é uma condição comum, que afeta até 28% da população. A articulação temporomandibular (ATM) é uma articulação complexa, composta por uma série de estruturas teciduais ósseas e moles, e cada uma das quais podem estar implicada em funções fisiológicas específicas e em síndromes associadas a patologias clínicas. O conhecimento da aparência da imagem normal da ATM, a sua aparição no exame radiológico e técnicas intervencionistas são úteis para fornecer uma contribuição diagnóstica eficiente. Anormalidades da ATM não podem ser avaliadas de forma confiável apenas por exame clínico, mas com o uso da RM podemos descrever alterações articulares que não eram vistas em qualquer outro método de imagem, indicando ser este o melhor método diagnóstico. Este artigo teve o objetivo de evidenciar a importância do uso da RM para diagnóstico das alterações da ATM, exemplificando diversas condições descritas com seu auxílio...

Emporomandibular disorders (TMD) is a common condition that affects up to 28% of the population. Temporomandibular joint (TMJ) is a complex articulation which consists of bones and soft tissue structures, each of which may be implicated in specific physiological functions and in clinical syndromes associated pathologies. Knowledge of the appearance of the normal image of TMJ, its appearance in the radiological examination, and interventional techniques are useful to provide efficient diagnostic contribution. TMJ abnormalities can not be evaluated only reliably by clinical examination, but with the use of MRI we can describe articular changes that were not seen in any other imaging method, indicating that this is the best diagnostic method for this task. This article aims to highlight the importance of MRI for diagnosis of impaired TMJ exemplifying various conditions described in the rescue...

Aplicações da impressão 3D na Ortodontia e Cirurgia bucomaxilofacial / Applications of 3D printing technology in Orthodontics and Oral and Maxillofacial Surgery

Ao longo da última década, avanços na prototipagem rápida vêm acontecendo, resultando no desenvolvimento de novas técnicas e abordagens. É o resultado de tecnologias de fabricação em 3D, como a estereolitografia (SLA), modelagem fundida (FDM) e, mais recentemente, a sinterização seletiva a laser (SLS). Entre suas aplicações, os guias cirúrgicos são gerados via computador e posteriormente fabricados por uma impressora 3D, sendo utilizado durante a cirurgia, possibilitando assim, posicionar de forma precisa os segmentos ósseos. A prototipagem também pode ser usada associada à tecnologia CAD/CAM (desenho assistido por computador) na Ortodontia, para personalizar a posição de braquetes e preparar guias personalizados para colagem ortodôntica indireta. Também, pode ser aplicada na customização e fabricação da aparatologia ortodôntica, através da fusão de imagens de modelos 3D. É notório que cada vez mais a prototipagem rápida vai se tornar uma rotina no dia a dia do ortodontista e do cirurgião, pois facilitam sobremaneira os procedimentos clínicos e possibilitam ao profissional ter maior previsibilidade dos seus resultados.

During the last decade, advances in rapid prototyping have resulted in the development of new techniques and approaches including 3D manufacturing technologies such as stereolithography (SLA), molten modeling (FDM), and more recently, selective laser sintering (SLS). Among its applications, the surgical guides are computer-generated, and then manufactured by a 3D printer for use during surgery, thus enabling precisely positioning of bone segments. Prototyping can be also used with CAD/CAM technology (computer aided design) in orthodontic brackets to customize its position and prepare customized guides for indirect orthodontic bonding. It’s also applied for customization and manufacturing of orthodontic appliance by the 3D model image fusion. It is clear that rapid prototyping will become a routine for the orthodontist and surgeon. It will facilitate the clinical procedures in such a way that professionals with have more predictable outcomes.